body {
    margin: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    overflow: hidden;
}

.navbar {
    background-color: #2c3e50;
    overflow: hidden;
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.navbar a {
    display: block;
    color: #ecf0f1;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
    transition: background-color 0.3s ease;
}

.navbar a:hover {
    background-color: #34495e;
    color: #ecf0f1;
}

.icon {
    display: none;
    user-select: none;
    cursor: pointer;
}

.avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    margin-right: 10px;
    background-color: #ccc;
}

/* 下拉列表容器样式 */
.dropdown {
    position: relative;
    display: inline-block;
}

/* 下拉内容样式，默认隐藏 */
.dropdown-content {
    display: none;
    position: absolute;
    background-color: #f9f9f9;
    min-width: 160px;
    box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
    z-index: 1;
    right: 0;
}

/* 下拉列表项样式 */
.dropdown-content a {
    color: black;
    padding: 12px 16px;
    text-decoration: none;
    display: block;
    text-align: left;
}

/* 下拉列表项悬停样式 */
.dropdown-content a:hover {
    background-color: #f1f1f1;
}

/* 显示下拉列表的类 */
.show {
    display: block;
}

@media screen and (max-width: 600px) {
    .navbar {
        display: block;
    }

    .navbar a:not(:first-child) {
        display: none;
    }

    .navbar a.icon {
        float: right;
        display: block;
    }

    .navbar.responsive {
        position: relative;
    }

    .navbar.responsive a.icon {
        position: absolute;
        right: 0;
        top: 0;
    }

    .navbar.responsive a {
        float: none;
        display: block;
        text-align: left;
    }
}